Your DUI, since you were under the legal drinking age, should have been a Class 2 misdemeanor, I believe, resulting in up to 30 days in jail and/or a $200 fine, but charges can be reduced or dismissed on a first offense, which is apparently what happened in your case.
Your possession and ingestion of marijuana are both Class 1 misdemeanors, if you had 2 ounces or less, and you should face not less than 15 days in jail and the possibility of a fine on a first offense. Since your marijuana charge comes after your DUI, however, both while you were under 21, I imagine you are facing the revocation of your driving privileges for a year or so, a sizable fine ($650-750, I think), and up to 120 days in jail (which generally is 80 days actual and 40 days suspended). A South Dakota attorney can give you a more accurate idea of what the penalties will be in your case, however, as I am not sure how the courts would figure the two Class 1 misdemeanors (possibly 3 with the paraphernalia charge) on top of your Class 2 misdemeanor DUI.
Second offenses are always taken more seriously than first offenses. Second offenses can lead to revocation of driving privileges, hefty fines and jail time, but possibly you can escape with no jail time with the successful completion of a court-approved chemical dependency program and, if you have liability insurance on your car, the court could potentially allow you to drive to a job or school or counseling (restricted driving privileges, in other words), as well. You should seek out the "decent" lawyer you had last time, to see if he can work more miracles for you.
